Combine flour, 1 Tablespoon granulated sugar, instant yeast and salt in the bowl of a stand mixer fitted with the dough hook attachment. Mix to combine. On low speed, add the sourdough discard and water until combined. Increase speed to medium and knead for 4-5 minutes until a smooth ball forms*. This will be a fairly sturdy dough and should not be sticky. You may need to add more water or more flour (1 Tablespoon at a time), depending on your sourdough discard, to reach the right dough consistency.

Grease a large bowl, transfer the dough to the bowl, and cover with plastic wrap. Let the dough rise for 90 minutes or until doubled in size.

Turn the dough out onto a smooth surface and divide into 8-10 equal pieces. 8 pieces will give you 8 large bagels; 10 pieces will give you 10 smaller bagels. Roll each piece in your palm to form a smooth ball, then use your thumb to press through the center of each ball, stretching the hole to form your bagel. Cover the bagels with a clean kitchen towel and let rest for 20 minutes while you prepare the next step.

Preheat oven to 425°F. Prepare 2 baking sheets lined with parchment paper and set aside. Bring a pot with 2 quarts of water and 2 Tablespoons granulated sugar to boil.

Place your bagels in the boiling water for 15-30 seconds on each side**. The bagels should float (if not, see notes below). You can likely fit 2-3 bagels in the pot at a time, just make sure there is enough room for them to float openly as they will expand. Remove from the boiling water using a slotted spoon and transfer to the prepared baking sheets. If needed, you can reshape the bagels a little after they've cooled.

Lightly brush the bagels with egg wash, then dip the top into your chosen toppings, if using (such as sesame seeds, poppy seeds, or everything bagel seasoning). You can also sprinkle the toppings onto each bagel.

Bake for 20-25 minutes or until golden brown. Let cool fully before slicing and serving.